Underreamer



w. w. WILSON.

UND'ERRE'AMER.

APPLICATION FILED JULY26. I916.

Patented June 1, 1920.

WILLIAM WILSON, OF LOS ANGELES, CALIFORNIA.

UNDERREAMER.

Specification of Letters Patent.

Patented June 1, 1920'.

Application filed .Tuly 26, 1916. Serial No. 111,437.

To all whom it may concern Be it known that I, \VILLIAM W. VVrLsoN, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in Underreamers, of which the following is a specification.

This invention relates to underreamers for enlarging well holes, and particularly underreamers used in enlarging oil well holes so that the tubing or casing'lowered in the holes as the drilling or hole production advances may be lowered, such underreamers serving in operation to reduce, remove or breakdown the shell or shoulder left heneath the casing in the operation of the drilling string which ordinarily only cuts the hole to a diameter equivalent to the inner diameter of the casing. Letters Patent on various types of underreamers have been reviousl issued, such as that covered by Jetters atent No.- 827,595, issued to E. (1. Wilson July 31, 1906. These underreame'rs have been extensively manufactured and to a large extent have taken the field in California and in foreign countries In my association with the exploitation of such underreamer, and in my extensive examination of the prior art, I have hit upon various combinations and inter-relations of reamer parts and features, one such entity, which I believe to satisfy the desiderata necessaril enterin into underreamer ractice constitutes the present invention. The invention has for its object the provision of an improved underreamer, being a radical departure from the prior art in combination and inter-relation and cooperation of parts and features and which will be superior in point of relative simplicity. and inexpensiveness of construction, taken in connection with durability, positiveness of operation,

reliability in service, facility in assemblingand dismantling, or disconnection of parts, and facility and convenience in repair or replacement or resharpening or remachining of parts andffeatures, including such facility in such treatment as will extend the length of life of the same without replacement of parts or members, and which will be generally superior in point of reaming,

efliciency and general serviceability.

With the above and other objects in view, the invention consists in the novel and useful provision, formation, combination, as

sociation, inter-relation and cooperation of parts, members and features, all as hereinafter described, shown in the drawing, and finally pointed out in claims. 7 a

In an accompanying application filed July 26, 1916, Serial Number 111,438, I have disclosed and described and separately claimed the article of manufacture constituting the body portion of the improved underreamer disclosed, described and claimed herein, and thus in said other application considered irrespective of the Fig. 3 is a fragmentary view, in elevation,-

of the lower portion of the reamer-body construction shown in Figs. 1 and 2, in elevation,"the cutters being indicated in dotted lines;

Fig. 4 is a view. similar to Fig, 3, and taken at right angles thereto;

Fig. 5 is a bottom end or plan-view of the underreamer body shown in the other figures; v I

Fig. 6 is a detail transverse sectional view, taken upon the line wa: Fig. 1, and looking upwardly; and 1 Fig. 7 is a detail inner face'view of one of the cutters or bits of the improved underreamer in detached position. a

Corresponding parts in all the figures are designated by the same reference characters. V v

Referring with particularity to the drawing, the improved underreamer is shown as a, hollow in' part or provided with a longitudinal chamcomprising an elongated bod flattened cylindrical chamber 10, which communicates with the bore 9, the latter be ing of less diameter than the chamber 10 so that a two-part shoulder 10 is provided at the upper extremity of such chamber 10*.

Cutters or bits B and C cooperate with the Such cutters further comprise each a body 13 beneath the shank 12, which same is provided with lateral shoulders 13 and 13 respectively, each of said shoulders having a bearing face, 13 and 13 respectively, whlch bearing faces are adapted to cotiperate with and bear upon the lugs 11, upon upper spreading bearings 11, such shoulders being likewise adapted at their upperinner edges 13 to co-act and cooperate with lower spreading bearings 11 upon such lugs 11; Each of such lugs is provided with two of such upper spreading bearings 11"? and with two ofsuch lower spreading bearings 11!, and the bearing faces 13 and 13 are adapted to traverse the upper spreading bearings 11 in the final portion of the action incident to expanding the cutters, and likewise in the initial portion of the action incident'to collapsing such cutters; while the upper edge portions 13 of the shoulders 13 and 13? engage with the lower spreading bearings 11 in the final stages of the collapsing action andthe initial stages of the expanding action of the cutters. D designates operating means for the cutters, being, in the main mounted and confined within the bore or chamber 9 in the body a, and same is shown as comprising a rod or'stem 14 operatively connected at its lower end 15 with the shanks 12 of the cutters, as by means of a T formation comprising members 15 takinginto the eyes or recesses 15 in the inner faces of the shanks at the upper ends thereof, such shanks being slightly beveled at their upper ends, from the tops thereof downwardly into the outer faces 12 thereof,

' as at 12, so as to permit the initiation of the collapsing and the termination of the expandingaction so as to accommodate the cutters. The rod 14 is spring-actuated, be-

ing surrounded by coil spring 16, such coil spring, or a washer 17 resting upon the same at its upper end, bearing againsta cotter pin or the like 18, detachably seated in the upper end. of the rod 15. The lower end of the coil spring 16 is confined by a removable stop 0, which in accordance with Letters Patent previously issued to E/C. Wilson for underreamer, No. 1,183,151, dated May 16, 1916, may comprise a key consisting of an elongated fiat body 19 provided at its lower edge with a depending wing or extension 20 fitting downwardly into the bore 9 of the body a, and passed into position within a transverse slot 21 formed in the reamer body a above the two-part shoulder 10", and likewise passed through an elongated slot 22 in the rod 14; the slot 21 being slightly enlarged vertically so as to permit the wing 20 to be passed into'positionas stated, and displaced therefrom, the upper corners of such key body likewise being beveled off as at 23 to. permit ready insertion or removal.

The upper-end of the body a may be provided with the usual threaded tapered joint member or pin 24'adapted to be received in a complementary threaded joint member,

not shown, upon the string of tools, or carexemplified by the particular embodiment of the invention therein disclosed.

' The cutters B and C are mounted upon the T head 15, and the rod 14 with its surrounding spring 16 and washer 17 and cot ter pin 18 is passed upwardly into the bore or chamber 9 through the open mouth I) at the lower end of the reamer-body. A suitable pilot key or wedge or other device is employed to pry up the lower end of the spring 16,and the detachable spring stop or key 0 is entered in the transverse slot 21 arid driven'under the spring until the wing or extension 20 rides into the bore 9, whereupon such key will be held in place by the compression of the spring cooperating with spreading bearings 11, the upper ends of I the shanks 12 bearing against'the two-part shoulder 10 at the upper end of the chamber 10. The cutters are thus in expanded condition or positions, and so held by -the action of the spring16. In order to dismantle.the reamer, a suitable wedge is applied beneath one end of the key 0, raising the key inthe slots 22 and 21, so that the wing '20-comes above the lower wall of the slot 21, whereupon a suitable implement may be used to drive the key endwis'e from 'its position in said slots and free of the reamer body a, whereupon the rod 14 and its spring and connected parts may be drawn downwardly and the cutter shanks withdrawn from the mouth I; and disconnected from the T head 15 for purposes of sharpening, dressing, or replacement. The detachable stop means or key 0 thus serves as means for operatively connecting the cut- Itoerg and the spring-actuated rod 14 with the When the reamer is to be introduced within the well hole, for use, the cutters B and C are brought together or collapsed by holding reamer-body a and drawing downwardly upon the cutters, until the shoulder edges 13 ride down upon the lower spreading bearings 13", as shown in Fig. 2, the

spring 16 being thus put under compression. The cutters in this performance teeter upon the T head 15, the cutter bodies 13 approaching each other beneath the lugs 11 and moving into a compass sufficiently small so that the reamer-body with such cutters may be '25 introduced within the casing or tubing in the wall and lowered therein until the cut ters reach a point beneath-the lower end of or shoe upon the casing, which is indicated fragmentarily at d in Fig. 1. Thereupon,

the cutters are "permitted to ride outwardly and upwardly at their shoulders upon the lower spreading bearings 11*, and to ride outwardly and upwardly at said shoulders upon the upper spreading bearings 11', under the urge of the compressed spring 16, which tends to elevate the rod 14 and such cutters, the cutters finally assuming the positions shown in Fig. 1. The reamer cutters are then in position beneath the casing,

which is raised somewhat above the shoulder'or shell in the walls of the hole. to be reamed, to the end that the cutters may have a zone in which to commence to operate.

Part of the cutter inthrust is taken by the T head 15, part likewise being taken by the upper spreading bearings 11. Out-thrust of the cutters is taken by the outer Walls of the chamber 10, and up-thrust is taken by the two-part shoulder 10*.

The reamer is now operated in the usual manner by reciprocating it vertically by means of the string or cable operated above the mouth of the hole by a walking beam or the like. When it is desired to discontinue the reaming operation and remove the reamer from the hole, the reamer is drawn upwardly by the string or cable, until the bodies 13 of the cutters, at their outwardly projected top portions 13 engage with the lower end of the shoe or the casing d, whereupon continued elevation of the reamer body will be accompanied by temporary arrest of the upward movement of the spring-actuated rod and connected parts of the cutters, which will travel at the shoulders of the cutters downwardly and inwardly across the upper and lower spreading bearings 11 and 11-, until the cutters come into the collapsed position as shown in Fig. 2, whereupon the cutters likewise, with the spring-actuated rod and connected parts, will be drawn on upwardly through the casing with the reamer-body a, and may be removed from tion which tends to weaken the cutters and cause breakage. "The cutter shanks are permitted to be formed of extreme thickness, inasmuch as they do not have to ride over any intermediate spreading portion or partition or wedge between such. shanks.

Furthermore, the shanks are entirely in; closed within the cylindrical mouth portion 10, which latter is devoid of any openings through which said cutter shanks might project, 1n accordance with certain previous practice. The cutters and such mouth (1 are likewise devoid of any of the shoulders, ways or dovetails which heretofore have been extensively employed in underreamers, for inter-relatingthe cutter shanks and the body of the reamer, and which dovetails, ways, etc.', are liable to fracture, as particularly in the so-called Double underreamer in which latter reamer likewise the objectionable tilting and sliding action of the shanks upon the means for connection with the -spring-actuated rod is found in practice,

and in which likewise an objectionable interposed wedge or partition or extension between the cutter shanks is found. In the present reamer, in contradistinction from such Double reamer, and 1n common withthe reamer of prior Letters Patent issued to E. C. Wilson, the mouth b of the reamerbody may be machined or cut back, up into the stock of the body, so as to renew the body in case of wear following long service, or in case of injury, it being understood that these devices are subjected to heavy service and are frequently employed beneath a heavy stringof tools-thousands of feet beneath the surface of the earth. Such remachining is likewise not possible with the lower edge of the mouth portion 10, and, if

. underreamer are exceptionallystrong, overcoming the many objections attaching to the cutters of the said Double reamer, which have inwardly directed shoulders formed by construction producing recesses in the inner faces of the shanks of the cutters which materially and often fatally weaken such cutter shanks. If a breakage of such cutters occurs in the use of the reamer the cutter parts frequently drop into the hole and require expensive and annoying fishing operations to remove them, or even at times drilling out such broken cutter parts or abandoning of the well hole.

I am not aware that any such combina tion and inter-relations of reamer-mouthincluding the continuous walled-chamber and the lugs 11 depending therefrom, together with the cutter bodies and shanks as constructed and as cooperating with such reamer-mouth-formation, has

ever been devised prior to my invention thereof, and the same provides many features and factors of advantage in superition to the construction and organization herein described and disclosed in the drawing, without departing from the true spirit of the invention and a fair interpretation thereof.

Having thus disclosed m invention, I claim-and desire to secure by etters Patent: 1. An underreamer comprising a body with a chamber in its lower end, which chamber is laterally closed around its periphery and opens downwardly at the lower end of the body, a pair of spreading lugs projecting downwardly from the body end at opposite sides of the chamber and each having upwardly diverging wedge faces,

the chamber and the lower opening of the chamberbeing free and-unobstructed for sole occupancy by cutters, oppositely disposed cutters having shanks extending up into the chamber, said cutters each having laterally extending shoulders to engage the wedge faces of the opposite spreading lugs, and cutter supporting and actuating means to which the cutters are pivotally attached at the upper ends of their shanks.

2. An underreamer comprising a body with a chamber in its lower end, which chamber is laterally closed around its periphery and opens downwardly at the lower end of the body, a pair of spreading lugs projecting downwardly from the body end at opposite sidesof the chamber and each having upwardly diverging wedge faces, the chamber and the lower opening of the chamber being free and. unobstructed for sole occupancy by cutters, oppositely disposed cutters havingshanksextending up into the chamber, said cutters each having laterally extending shoulders to engage the wedge faces of the opposite spreading lugs, said shoulders being located on the cutters 'in positions outwardly removed from the inner opposin faces of the cutters and the cutters extending inwardly past said shoulders and between the opposite spreading lugs, and cutter supporting and actuating means to which the cutters are pivotally attached at the upper ends of their shanks.

3. An underreamer comprising a body with a chamber in its lower end, which chamber is laterall closed around its periphery and opens ownwardly at the lower end of the body, a pair of spreading lugs projecting downwardly from the body end at opposite sides of the chamber and each having upwardly diverging wedge faces, the chamber and the lower opening of the chamber being free and unobstructed for sole occupancy by cutters, oppositely disposed cutters having shanks extending up into the chamber, said cutters each having laterally extending shoulders to engage the wedge faces of the opposite spreading lugs, said diverging wedge faces of the spreading lugs being situated on opposite sides of a vertical plane central of the body and the cutters being located symmetrically with respect to said plane; and cutter supporting and actuating means to which the cutters are pivotally attached at the upper ends of their shanks so that the cutters swing on pivotal points located as near to their outer surfaces as to said. central plane.

4;. An underreamer comprising a body with a chamber in its lowerend, which chamber is laterally closed around its periphery and opens downwardly at the lower end of the body, a pair of spreading lugs projecting downwardly from the-body end at opposite sides of the chamber and each having upwardly diverging wedge faces, the chamber and the lower opening of the chamber being free and unobstructed for sole occupancy by cutters, oppositely disposed cutters having shanks extending up into the chamber, said cutters each having laterally extending shoulders to engage the wedge faces of the opposite spreading lugs, and cutter supporting and actuating means to which the cutters-are pivotally attached at the upper ends to their shanks; each spreading lug having a'lower pair of upwardly diverging wedge faces making a comparatively obtuse angle with each other and an upper pair of diverging wedge faces making a comparatively acute angle with each other, and the cutters being forced lower end of the body, a

lugs projecting downwar y from the body' outwardly by upwardtravel'over the last mentioned faces to a position where the outer surfaces of their shanks are forced against the walls of the chamber.

5. An underreamer comprising a body with a chamber in its lower end, which chamber is laterally closed around its periphery and opens downwardly at the lower end of the body, a pair of spreading lugs projecting downwardly from the body end at opposite sides of the chamber and each having upwardly diverging wedge faces, the chamber and the lower opening of the chamber being free and unobstructed for sole occupancy by cutters, oppositely disposed cutters having shanks extending up into the chamber, said cutters each having laterally extendingshoulders to engage the wedge faces of the opposite spreading lugs,

said shoulders being located on the cutters in positions outwardly removed from the inner opposing faces of the cutters and the cutters extending inwardly past said shoulders and between the opposite spreading lugs, said diverging wedge faces of the spreading lugs being situated on opposite sides of a vertical plane central of the body and the cutters being located symmetrically with respect to said plane; and cutter supporting and actuating means to which the cutters are pivotally attached at the upper ends of their shanks so that the cutters swing on pivotal points located as near to.

their outer surfaces as to said central plane.

6. An underreamer comprising a bo y with a chamber in its lower end, which chamber is laterally closed around its periphery andopens downwardly at the air of spreading end at opposite sides of the chamber and each having upwardly diverging wedge faces, the chamber and the lower opening of the chamber being free and unobstructed for sole occupancy by cutters, oppositely disposed cutters having shanks extending up into the chamber, said cutters each having.

laterally extending shoulders to engagethe wedge faces of the opposite spreadmg lugs,

said shoulders being located on the cutters in positions outwardly removed from the inner opposing faces of the cutters and the cutters extending inwardly past said shoulders and between the opposite spreading with a chamber in its lower end, which.

chamber is laterally closed around its periphery and opens downwardly at the lower end of the body, a pair of spreading lugs projecting downwardly from the body end at opposite sides of the chamber and each having upwardly diverging wedge faces, the chamber and the lower 0 ening of the chamber being free and uno structed for sole occupancy by cutters, oppositely disposed cutters having shanks extending up into the chamber, said cutters each having laterally extending shoulders to engage the wedge faces of the opposite spreading lugs, said shoulders being located on the cutters in positions outwardly removed from the inner opposing faces of the cutters and the cutters extendlng inwardly past said shoulders and between the opposite spreading lugs, said diverging wedge faces of the spreading lugs being situated on opposite sides of a vertical plane central of the body and the cutters being located symmetrically with respect to said plane; and cutter supporting and actuating means to which the cutters swing on pivotal points located as near to their outer surfaces as to said central plane; said cutter supporting means embodying a T-bar having an enlarged head be- WILLIAM W. WILSON.

Witnesses ALFRED H. DAEHLER, -FBANOIS L. Iscnroo. 

